New Features in Java 1.2

Java 1.2, also known as Java 2, was released in December 1998 and introduced several significant features and improvements.

Key Features Introduced in Java 1.2:

• Swing GUI Framework: A more flexible and customizable set of GUI components compared to the older AWT.
• Collections Framework: Introduced a unified architecture for representing and manipulating collections, including interfaces like List, Set, and Map, along with their implementations.
• JIT (Just-In-Time) Compiler: Significantly improved Java's performance by compiling bytecode to native machine code at runtime.
• strictfp Keyword: Ensured floating-point calculations are strictly consistent across different platforms.

Code Example: Using the new Collections Framework

public class Java12Example {

    public static void main(String[] args) {
        // Using the new ArrayList class from the Collections Framework
        List cities = new ArrayList();
        cities.add("New York");
        cities.add("London");
        cities.add("Tokyo");

        // Using the new HashMap class
        Map cityPopulation = new HashMap();
        cityPopulation.put("New York", new Integer(8336817));
        cityPopulation.put("London", new Integer(8982000));
        cityPopulation.put("Tokyo", new Integer(13929286));

        // Iterating over the List
        System.out.println("Cities:");
        for (int i = 0; i < cities.size(); i++) {
            System.out.println(cities.get(i));
        }

        // Iterating over the Map
        System.out.println("\nCity Populations:");
        Iterator it = cityPopulation.entrySet().iterator();
        while (it.hasNext()) {
            Map.Entry entry = (Map.Entry)it.next();
            System.out.println(entry.getKey() + ": " + entry.getValue());
        }
    }
}

Detailed overview of Java 1.2 in relation to its previous and next versions: